My apologies. I'm probably making a mistake somewhere, but I noticed a small issue whilst I'm playing a pattern.
The song playback arrow thing seems to be slower than the actual playback during certain pattern size instances. During my tests, I found that a pattern length of 256 caused the song playback arrow to move at half the speed it's supposed to go at, while a pattern length of 16 caused it to become even slower.
The following video was taken on a MacBook Pro, using MacOS version 10.15.3 (Catalina), demonstrating the issue I ended up facing. My apologies in regards to the quality of it.
Aside from that, thanks for making this software. It's been really fun to use, and I'm glad that it exists.